Add 4/5 and 45/12, Solve 4/5 + 3 9/12 as a fraction

Add 4/5 and 45/12

1^st number: 4/5, 2^nd number: 3 9/12

4/5 + 45/12 is 91/20.

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 12 is 60

Next, find the equivalent fraction of both fractional numbers with denominator 60
For the 1st fraction, since 5 × 12 = 60,
4/5 = 4 × 12/5 × 12 = 48/60
Likewise, for the 2nd fraction, since 12 × 5 = 60,
45/12 = 45 × 5/12 × 5 = 225/60
Add the two like fractions:
48/60 + 225/60 = 48 + 225/60 = 273/60
273/60 simplified gives 91/20
So, 4/5 + 45/12 = 91/20
In mixed form: 411/20

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